Today I had the displeasure of removing yet another instance of Antivirus XP 2008. It's a scam antivirus program that is nearly impossible to remove, at least, until I found my new favorite antispyware program: Malwarebytes Anti-Malware.
Spybot stole the crown from Ad-Aware not too long ago because of its more open licensing and the fact that Ad-Aware has started to become bloatware. I'll still be using Spybot, but probably not as much now since Malwarebytes found so much more crap after I ran Spybot on my client's computer today.
My favorite spyware prevention software remains the same: Firefox and SpywareBlaster.